Organosilane compounds are commonly used in the tire manufacturing and rubber vulcanizates industries. Typically, these compounds act as bonding agents in vulcanizable rubbers containing reinforcing filler material such as silica and carbon black.
A number of different methods have been proposed for producing such compounds. For example, U.S. Pat. No. 3,842,111 to Meyer-Simon et al. describes a process for the production of bis(alkoxysilylalkyl)oligosulfides from the corresponding alkoxysilylhalides and alkali metal oligosulfides, preferably in alcoholic solution.
U.S. Pat. No. 4,072,701 to Pletka proposes a method of making bis-(alkoxysilylalkyl)oligosulfides by the reaction of alkoxysilylalkylhalides, metal or ammonium hydrogen sulfides and sulfur. This reaction, however, produces quantities of a toxic by-product, namely hydrogen sulfide, and is therefore not deemed industrially practical.
U.S. Pat. No. 4,129,585 to Buder et al. describes a method of making bis-(alkoxysilylalkyl)oligosulfides by the reaction of an alkali metal alcoholate, with an alkoxysilylorganylhalide, metal or ammonium hydrogen sulfide, and sulfur in the presence of an organic solvent.
U.S. Pat. No. 4,507,490 to Panster et al. describes a method of making sulfur-containing organosilicon compounds by dissolving a metal hydrogen sulfide in an organic solvent, treating with an alkali metal and optionally sulfur, and directly subsequently further reacting with a haloalkylsilane.
There remains, however, a need in the art for an industrially practical, one-kettle reaction method of producing sulfur-containing organosilane compounds which results in high yield without the production of toxic by-products.